Chlorine is used in water for

The freezing point of heavy water at $1 \ atm$ pressure is: (in $^{\circ}C$)

Melting point,enthalpy of vaporisation and viscosity data of $H_2O$ and $D_2O$ is given below.

$Property$	$H_2O$ vs $D_2O$
$Melting$ $point/K$	$273.0$ vs $276.8$
$Enthalpy$ $of$ $vaporisation$ $at$ $(373 \ K) / kJ \ mol^{-1}$	$40.66$ vs $41.61$
$Viscosity/centipoise$	$0.8903$ vs $1.107$

On the basis of this data,explain in which of these liquids intermolecular forces are stronger?

Which of the following is heavy water?

In the charring process, concentrated sulfuric acid reacts with sugar to give sugar charcoal. What is the role of conc. $H_2SO_4$ in this reaction?

Oxygen was discovered by